Method and apparatus for rolling metallic strip



. 14,1937 Y .L MONTGOMERY Er AL v2,102,184

` METHOD ANDAPPARATUS FOR ROLLING METALLIC STRIP Filed sept. 2o, 1935 v 4 sheets-sheet 1 WITNSSEJ INVENTOR;

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Dec. 14, 1937. J. E. MoNTGoMERY Er Al. 2,102,184

` METHOD AND APPARATUS FOR ROLLING METALLIQ STRIP Filed Sept. 20, 1935 4 Sheets-Sheet 2 DeC 14j 1937-A JQE. MONTGOMERY ET AL A 2,102,184 f METHOD AND APPARATUS FOR ROLLING METALLIC STRIP 14,1937. L E. `MONTGOMERY ET AL 2,102,184

METHOD AND APPARATUS FOR ROLLING METALLIC STRIP Filed sept. 2o, 1935? u v ,4 sheets-sheet 4^ W/T/VEJJEJ A f a: INVENTOR 1 M077/ y A M ATTORNEYJ Patented Dec.` 14,` 1931 lUNITED STATES PATENT i OFFICE METHOD A Nfn APrAaA'rus Foa ROLLING METALLIC STRIP Julian E. Montgomery, cleveland, Ohio, and .101m -J'1, Flaherty, Pittsburgh, Pa., assignors to `United Engineering & Foundry Company, Pittsburgh,

` n Pa., a corporation o! Pennsylvania V i, 'application september zo, i935, semaine. 41,460` n,

, n ,lsolsimn This invention pertains to` thecold rolling of metallic strip, and while notinecessarily so limited relates more particularly toan improvement in method and apparatus for the cold rolling of strip steel. f

Strip steel and the like is customarily, made by rolling a hotslab tostr'ip form in a continuous i hot strip mill and then reducing it to thepfinished "dimensions in a cold finishing mill.` vWhile there fil)` are a number of different kinds of cold mills used Y for this purpose, they may be classified generally as of three different types. These are the continuous type of mill in which a pluralityfof tan-` demly arranged roll stands is used and Vthrough l5 which the strip is passed insuccession, the'singie roll `stand `millwhichis operated inone direction "only and through which the strip is repassed as" many times as may be required, and

is `passedqback andv forth until finished.

" `A` fault common to all of these prior mills where they are providedwith means for tensioning the strip, in accordance with a well-known practiceas it ispassed through them, is that 5 they are incapable oftensioning and working a ,-21 be shut downwheneverany part of the mill goes wrong. In the priorsingle stand mills in` which the strip is rolled Onefor more times in the same direction thereisalso thetfrther disadvantage that considerabletime islost yin transferring the "4. strip around the `mill between passes as well as the fact thatoonsiderable transfer apparatus is "required'for such purposes In the reversing type mills it is theusual practice to engagethe ends of the stripfinreels or winding devices,` on which p. 1 the strip is coiled, at the two v,sidesof the mill and to never `release them `during the rolling opera-` tion. This results in such portions` of the Strip not beingl worked-at all.

` With the ioregoingginlmind, itis theyprimary object of this inventionto provide an improved method and apparatus for the cold rolling of strip material `under tension,` which is efiicient and economical to both install and-operate, and which greatly reduces the amount of Vwaste, material ordinarily produced` at the ends of the strip, i

the single reversible standmill in which the strip V they represent exceedsin value the entire labor Amore specific object is to provide for the cold rolling of strip steel, orfthe like, in-a single rel versing roll stand and for passing the entire strip through the millreachtime it is worked while at the same timemaintainingit under tension from ,end to end during theentire rolling operation.

Another objectisto provide a reversiblecold p mill which is'equippedto' pass the strip all the way through the mill each time it is rolled and to reenterV itin themill without releasing the tension in the coil on either side of the mill.`

These and various other objects as well as vari-- ous other novel features and advantages of the invention will be apparent when the following detailed description is read in conjunction with theaccompanying drawings, of which Fig. 1 is a planview of a mill layout designed to practice the invention; Figs. 2 and 3 sectional views taken through the `centerof the mill iliustratedin Fig.

`l showing it operatingV in opposite directions: Fig.

4; a sectional view to enlarged scale of the striphandling mechanism at one side of the mill showing the sticker' in position to enter the strip into the mill rolls; Fig.` 5 an elevational `view looking into the mill end of one of thecombination striptensioning and feeding stickers; Fig. 6 a plan viewof one of the reel drums together with its line VII- VII of Fig. 6; Fig. 8 a sectional view of one of the hydraulic motors used for `actuating `support and drive; Fig. '7 a section taken on the the feeding and tensioning stickers together with its operating controls showing the-.position of the plunger of the motor` and its control valves when the` sticker is idle and in its outermost position: Fig. 9 a view similar to Fi`g."8 butshowing the position of, the control valves and the motor plunger whenthe sticker is being moved toward themill; and Fig. l0 another view similar to Fig. 8 showing the position of the control valves when the plunger is being operated as a dash-pot or brake to resistthe movement of the sticker away from the mill.

In accordance with the inventionl a single` reversing roll stand I of the 4-high type, asillus- 4trated in the drawings,`ispreferably all of the rolling apparatus that is used to perform the cold rolling Operations. Fordriving such stand it is equipped with a reversible motor 2, while for han- Hdling the strip passed through it, suitable, coilsupporting i and strip-rewinding apparatus, designated generally bythe reference characters 3 and 4, is provided.

This latter apparatus mayobviouslytakevarious forms, but'as shown it comprisesa pair of portable winding drums` 5 which are detachably supported in a pair of coil boxes 6 and 1 suitably spaced from the roll stand. Preferably the strip is wound on one of these drums after it leaves the. hot mill and is delivered thereon to one of the coil boxes 6 or 1, an empty drum 5 being provided in the other coil box. Referring more particularly to Figs. 1, 6, and '7, the drums 5 are provided at their ends with supporting and driving necks or trunnions 8 and the coil boxes 6 and 1 with recesses 9 in their side wallswherein such necks are detachably held in place by suitable retainers Ill. For driving them suitable driving motors II are provided adjacent one end of each of the coil boxes, being connected to the drive shafts I2 equipped with suitable couplings I3 which are adapted to be detachably connected to theends 6a of the drum necks 8, such ends being properly developed for this purpose. To also facilitate the rotation of the drums the necks 8 are equipped with roller bearing sleeves I4 which arevin turn provided with anges adapted to straddle the wall structure of the coilboxes and hold them against axial displacement.

In `their details of construction the winding drums 5 may be widely varied so long as they are adapted to effectively engagethe end of the strip to. permit a tension being applied to it and to also readily release the strip when such is desired. In

addition, they may be either automatically or manually operable, and those' shown are of the latter type in which the end of the strip is inserted in a slot I5 and releasably locked in place by an axially adjusted wedge acting type of clamping bar I6.

For feeding the ends of the strip into the mill rolls and also tensioning `it as soon as it is engaged in the mill, as well as preventing the tension in the winding reel from being relieved when the trailing end of the strip leaves the mill, a pair of strip-sticking and tensioning devices 23 and 24, referred to hereinafter as stickers, is provided at the two sides of the mill adjacent the working rolls. As shown, these devices each comprise a main frame 25 which is mounted for guided reciprocatory movement in a horizontal plane toward and from the mill rolls on a pair of `guide bars 26 secured to the inner faces of the roll housings 21, the frame 25 being provided with grooves 30 in its side walls 29 for the reception of such bars. The upper surface of this frame is made flat and is disposed in the plane of the roll pass to support the strip. Above it there is arranged for vertical reciprocatory movement between its side walls 29 a shoe 3| which is disposed to clamp the strip against the frame so that together they are operable for sticking the strip into the mill rolls and tensioning it after it is engaged in the rolls.

To'operate each of these clamping shoes 3| a pair of pressure-applying and lifting motors 32 is mounted on a cross member 33 secured to the side Walls 29 of the frame 25. In the form shown these motors may be either of the hydraulic or electromagnetic type provided with plunger or armature-operated connecting rods 34 which are connected to brackets 35 located at the top of the shoe 3l adjacent its ends. All that is yessentially required of these motors is that they have suilicient power to lift the shoes when desired and to exert the necessary pressure upon them to give the gripping action on the strip needed for feeding it into the mill `and for tensioning after it is engaged in the mill.

For moving the stickers A23 and 24 toward the milll hydraulic motors 36 are provided, being supported in the uprights 31 which comprise the supports for idler rolls 38 arranged in the plane of the roll pass between the stickers and the coil boxes to facilitate the delivery of the strip from the winding drums to the stickers and from the stickers to the winding drums. 'I'he plungers 39 of these motors, two of which are associated with each sticker, are connected by connecting rods 4I and links 42 to the mid-section of a pair of levers 43. These levers are in turn secured at their lower ends to 'xed pivots 44 and pivotally connected at their upper ends by links 45 to the under side of the frames 25 adjacent the outer end of the latter. Consequently when the plungers 39 are forced outwardly the stickers are actuated toward the mill.

To limit the forward movement of the stickers, v

arms 46 are provided on the outer ends of the frames 25 and disposed to project over the outer face of the mill housings. In these arms suitable adjusting screws 41 are threadably mounted and adapted to engage the mill housings and determine the inward movement of the stickers as may be desired.

To also provide for insuring against the strip passing otherwise than through the stickers when it issues from the mill, as well as remove foreign material from the mill rolls, a pair of wiper guides 48 and 49, which are disposed to bear against the surface of the working rolls, is pivotally mounted on the mill ends of frames 25 and shoes 3l. The upper of these guides is resiliently maintained in contact with the upper mill roll by means of rods 5I secured to the mid-section thereof and springs 52 mounted on such rods below their 1reads 53 and above brackets 54 on the shoes through which the rods project. The lower of these wipers, 49, is

`held in contact with the lower working roll by gravity.

As schematically illustrated in Figs. 8, 9, and i0, the pressure supply for the sticker-actuating motors 36, which may be of any suitable form, is furnished by a supply line 55 and the exhaust of the motors disposed of by anoutlet pipe 56. In these pipes, which are connected respectively to the inlet and outlet ports 51 and 58 at the ends of the motor cylinders', there is provided a pair of two-way valve casings 59 and 6I equipped with valves 62 and 63 and cooperating ports 59a and Gla. which are connected together* by a pipe 64. With this arrangement when the valves 62 and 63 arel adjusted as'shown in Fig. 8, the pressure supply for the motors is shut off, and when adjusted as shown in Fig. 9, it is communicated to the rear end of the motor cylinders to' force the piston 39 outwardly and the associated stickers toward the roll stand.

For a purpose which will be presently more fully described, one-way check valves 65 are provided in the exhaust lines 56 between the motor cylinders and control valve casings 6I. These check valves, which may-be of any well-known construction, are adapted to permit free flow of the motor pressures out ofthe motor cylinders by way of the exhaust outlet, but only restricted flow in the reverse direction. Hence when the valves 62 and 63 are adjusted to the positions shown in Figs. 8 and 10 movement of the pistons 39 toward the rear of the motor cylinders is determined by the pressure on the pistons and the setting of thecheck valves 65. Thus the motors are adapted to resist the rearward or outward movement of'the stickers.

In practicing theinvention a loaded drum 5 is mounted in one of the coil boxes, say the coil d from the top of the coil. It is then connected by lthe coupling I3' to the drive shaft I2 associated therewith. The motor l l connected to such shaft,

"which is of the reversible type, is then excited to `operate insa direction to unwind the strip from `the drum untilthe` free end of the coil is passed over the associated idlerroll 38' and through the adjacent sticker 23`^pre`viously actuated to its louter position.` When the forward end of the stripp'rojects beyond the @forward end of the sticker 23 far enough 4for the sticker `to `forcesuch end into the mill rollswhen it is moved to its for- On" issuing from ward position, the shoe 3i is then clamped against thestrip by the motors 32, ,The sticker isthen movedtoits feedingpositionby its actuating motors ,36, the mill, of course,`being`previou'sly set in `motionin the proper direction by its driving motorZ. s Ass'oon"` as the"working rolls begin to pull the strip through the mill it is placed under `tension `by the sticker, and the sticker, being stationary, `functions as adrag. To'maintain this tension after thelrollingigets under way,"andfwithout the yaid `of the sticker, which for many purposes may be desirable, a brake I2a is "provided on Veach of the drive shafts i2 to resist the rotationofthe unwinding drum 5,. This may, of course, also be accomplished by dynamically or regeneratively brakingthe rotationof the motor associated with the mill the leading end of the strip is passed through the sticker *24,whichgis previouslyactuated to a point adjacent the mill,

and engaged in the clampingmeans o1' the drum Y fi` comprising` the winding reel. Once itis so engaged the motor vi i for the latter"drum is exfcited to cause the drum to wind the strip thereon and also tension the forward end to the extent .desired.` `When `the last turnlof the strip unwinds from the unwinding drum 5 at the front `of the mill, the entering sticker 23, if previously re leased, is reclamped upon thestrip to maintain the tension in the strip until the trailing end thereof is pulled from the sticker; Hence all of "the strip except the very small length between the sticker and mill is maintainedV under tension while it is being rolled. s v

Slightly beforethe tail-end oi the strip leaves the inill rolls the shoe 3| "of the sticker24 at the` discharge side of the mill .is actuated tb Aengage tliestrip and,as the Valves62 and 63 of the sticker motors 36 are previously Vadjusted to the positions `shown `in Figs.f9 and` 11the sticker 24 is now pulled` back with` the strip `and against the re- "sistance offered bythe enclosed fluid in the cylinllder. This resistanceserves to' maintain theA ten-` `sion in the strip'while the tail-,end is out of the mill. The sticker is then operated in the reverse direction to reinsert the tail-endof` the strip back into the mill for reverse-rolling; To prevent'sthe winding motor I l from drawing the strip through the sticker 24, its associated brake maybe applied and its current supply reversed whenitis stopped,` ,n s s Y Before repassing the strip through the mill,` its working rolls are adjusted` by the screw-down mechanism 12 provided for such purpose and the driving motor 2 of`1the mill reversed; When this `is done the sticker 24 `is actuated to stick the end of the strip back into the mill and the previously described operations repeatedin the reverse direction. These operations; are, of course, repeated as many times as may be desired and the fin# ished coil removed from the coil boxV in which it lized to remove the fish-tails which form on the ends of `strip to facilitate the entry of the strip in `thegripping elements of the winding drums. Such shear, as shown in full and dotted lines, may be arranged on either side of the drums. y'I'he controls `for thedifferent motors, which have not beenshown in detail as such is deemed unnecessary, may, as will be readily appreciated by those skilled in the art, be made in various ways so long as they arecapable of providing the proper control for such motor, and if desired may also be made to operate automatically wherever practical. Y t s n l According Vto thev` provisions of the patent statutes, we `have explained the principle and mode of operationpf vourinvention, and have illustrated and described what we now consider to bezitsbest embodiment. vHowever, we desire to have it understood that, within the scope of the `appended claims, the invention may be practiced otherwise than as specifically illustrated and described. i i

c We claim: i r

. l. A strip mill comprising arroll stand, means, for drivingsaid roll stand in opposite directions; means at opposite sides oi said stand for handling the strip and tensioningit while it is engaged in the roll stand, `meansinterposed, between said ,haridling means and the roll stand and operative.l adjacent the roll pass thereof` for gripping the strip` and positively feeding it into i for drivingthe rolls jthereof in opposite directionsmeans at opposite sides of the mill for delivering the strip `to the -mill rolls and also tensioning it, and strip engaging `means interposed between said strip-delivering` and strip-tensioning means at both sides of the mill and movable to and from the mill for positively feeding the leading end of the srip into the rolls andapplying a back tension thereto as soon as Vthe strip is engaged inthe rolls.

4. The method of rolling metal strip which comprises passing the `strip all the way` through the working rolls of the mill in opposite directions, applying a back tension to it as soon as thea first end` is entered in the mill andconstantly maintaining said tension insboth Vdirections `of rolling from the instant the stripisrst entered issuesfrom the mill in each direction. s

5. A strip mill comprising a roll stand, means fordriving the rolls of said stand in opposite directiens, a coil-supporting reel at each side ost" saidl stand. means for driving and braking said reels'to wind and tension` the strip when `passing through the roll stand in either direction, and strip-engaging means interposed between said reels and the roll stand which is adapted to positively feed the ends ol' the strip into the mill rolls and tension it as soon as it is engaged between the rolls and to also grip the trailing ends as they leave the mill and also feed them back into the mill rolls without releasing the tension exerted therein by the reels.

6. 'Ihe method of rolling metal strip which comprises winding the strip to be 'rolled in the form of a'coil, passing it from the coil into the working rolls of a rolling mill, applying a back tension to it as soon as it enters the mill and maintaining said tension thereon until its trailing end enters the mill, winding the strip into a coil as it leaves the mill and at the same time applying a tension to it, gripping the trailing end as it leaves the mill and preventing the tensionA in the coil from being substantially relieved, and then repassing the strip in the same manner through the mill in the reverse direction.

7. A strip mill comprising a roll stand, means for driving the rolls of said stand in opposite directions, a coil-supporting reel at each side of said stand, means for driving said reels to wind the strip thereon as it issues from the roll stand and applying a tension thereto, means for braking said reels to exert a tension on the strip as it is being unwound from the reels, and movable means between each of said reels and the roll stand for gripping the trailing end of the strip as it leaves the roll stand to maintain the tension therein and positively feed it back into the rolls.

8. The method of rolling metal strip which comprises positively feeding the strip into the working pass of a rolling mill, applying a backl tension vto itA as soon as it is engaged in the.

mill, applying a tension to it as it leaves the mill, gripping the strip adjacent the mill just before its trailing end leaves the mill, adjusting the working pass of the mill, and then reinserting the strip between the mill rolls without re- 'leasing the tension therein and repassing it through the mill in the same fashion in the reverse direction.

9. In a strip mill, a roll stand, means for driving the rolls thereof in opposite directions, a combination sticker and drag mounted for horizontal reciprocation on each side of said roll stand adjacent the working rolls thereof, means for operating said stickers to engage the strip, means for positively moving said stickers toward the stand to feed the ends of the strip into the mill rolls, and means for resisting the movement of said stickers away from the roll stand.

10. In a strip mill, a roll stand, means for driving the rolls thereof in opposite directions, a combination sticker and drag mounted for horizontal reciprocation on each side, of said roll stand, hydraulic means for actuating said stickers toward said roll stand. and means for controlling said hydraulic means to resist the movement of said stickers away from said stand.

11. A strip mill comprising a roll stand, means for driving the rolls thereof in opposite directions,

a coil box arranged on opposite sides of,said

stand, a driving motor associated with each of said coil boxes, a removable coil drum mounted in each of said coil boxes, means for releasably connecting said coil motors to said coil drums, means for braking said drums, a combination sticker and drag mounted for horizontal reciprocation adjacent each side of said roll stand between it and said coil boxes, means for engaging and disengaging said stickers, and means for moving said stickers toward and resisting their movement from the roll stand.

12. In combination with a strip mill, an uncoiier at one side of said mill adapted to exert a restraining tension on the strip entering said mill, a coller at the other side of said mill adapted'to exert a forward tension on the strip delivered by said mill, and movable means disposed between said coller and said mill which is adapted to engage the tail-end of the strip as it is leaving the mill rolls and both maintain the tension on the coiled strip and feed the end thereof back into the mill for reverse rolling.

13. In combination with a strip mill,l means for coiling strip under tension while it is being rolled, and means disposed between said coiling means and the mill which is operative to maintain the strip under tension from the time it leaves the rolls until it is reentered in said mili and whereby the-strip is constantly maintained under tension until the rolling is completed.

14. In combination with a strip mill, means for coiling strip under tension while it is being rolled, means cooperating with said coiling means for maintaining the tension in the strip after it leaves the rolls of said mill. and means for operating said last-mentioned means to feed said strip back into said mill.

15. In combination with a strip mill, means for engaging and tensioning a piece of strip leaving said mill, and means interposed between said last-mentioned means which is operative to engage the strip just before its tail-end leaves the rolls and maintain the tension therein-until the end thereof is reinserted in the mill by said lastmentioned means.

16. The method of reducing metal strip which comprises-rolling the strip between the working rolls of a mill, coiling said' strip under tension as its leaves said mill, and gripping the trailing end of said strip as it leaves the mill without permitting the tension in the strip to be released, said gripping action being yieldable in a direction longitudinal of the strip.

17. The method of rolling strip in a reversing mill having releasable horizontally movable clamps on both sides of the mill which comprises entering the leading end of the strip through and beyond the clamp on the entering side of the mill, engaging said clamp and moving it toward the mill to feed the protruding leading end of the strip between the mill rolls and through the released clamp on the opposite side of the mill, coiling the strip under ytension beyond said lastmentioned clamp, engaging said last-mentioned clamp before the trailing end of the strip leaves the mill to maintain the tension therein, and

,moving said last-mentioned clamp toward the mill to feed the strip back into the rolls.

18. 'I'he method of reducing coiled metal strip which comprises passing the strip from the coil into the Working rolls of a rolling mill, applying a back tension to it as soon as it enters the mill and maintaining said tensionl thereon until its trailing end enters the mill, coiling the strip under tension as it leaves the mill. gripping the trailing end before it passes out of the mill and re-' turning it to the mill without allowing the tension in the strip to be released, and then repassing the strip in the same manner through the mill in thereverse direction.

JULIAN E. MONTGOMERY. JOHN T. FLAHERTY.

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